As much as I would love to increase our current storage capacity, I think we should still work toward short term goals before doing something long term. Making a shield increases our longevity (1-3 blocking atm), while a sword would increase our damage potential (3-7 atm).
I'm not convinced that we need the attack power atm (I rather get a weapon that has an effect tbh (if there are any)), and right now we have 2/4 of our scroll slots open. One is near useless at this time (EQ- Seems like an Elemental vs Elemental scroll), and another is valuable. Need be, we could get rid of the EQ scroll (Too limited use if we gain more wide range options). The space would be nice, but not currently neded (if we get an average of 1 item per new area explored, and we'll eventually use items later). The fact that we'd be getting a "non- Elements related item" might be too good to pass up.
But I vote for the shield. Longevity is right now what we need so we need not rest too much, IMO.
I'll readily change my vote if you anyone convince me. I'm 60/40/0 Shield/Carry/Sword, so it can happen.